Ballast box



FIG. 1 is a top perspective view of a ballast box showing my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a front side view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a back side view thereof; and,

FIG. 7 is a right side view thereof. 

The ornamental design for an ballast box, as shown and described. 